Method and structure for aligning mechanical based device to integrated circuits

• US 20050255666A1
• Filed: 05/11/2004
• Published: 11/17/2005
• Est. Priority Date: 05/11/2004
• Status: Abandoned Application

• Current Assignee: Miradia Inc. (Walsin Lihwa Corporation)
• Original Assignee: Miradia Inc. (Walsin Lihwa Corporation)
• Inventors: Yang, Xiao Charles
• Application Number:
  US10/843,793
• Publication Number:
  US 20050255666A1
• Time in Patent Office: Days
• US Class Current: 438/401
• CPC Class Codes: B81C 2203/051 Active alignment, e.g. using internal or external actuators, magnets, sensors, marks or marks detectors
• CPC Class Codes: B81C 3/004 Active alignment, i.e. moving the elements in response to the detected position of the elements using internal or external actuators
• CPC Class Codes: H01L 21/187 by direct bonding

Abstract

A method for bonding substrates together. The method includes providing a first substrate comprising a first surface. The first substrate comprises a plurality of first chips thereon. Each of the chips has integrated circuit devices. The first substrate includes a first alignment mark on the first substrate and a second alignment mark on the first substrate. The method also includes providing a second substrate comprising a silicon bearing material and second surface. The second substrate comprising a plurality of second chips thereon. Each of the chips comprises a plurality of mechanical structures. The second substrate has a first silicon based pattern on the second substrate and a second silicon based pattern on the second substrate. The method includes moving the first alignment mark of the first substrate to the first silicon based pattern on the second substrate and aligning the second alignment mark of the first substrate to the second silicon based pattern on the second substrate. A portion of at least one of the first substrate or the second substrate is illuminated with electromagnetic radiation. The method includes detecting a portion of the electromagnetic radiation and using the detected portion of the electromagnetic radiation to align the first substrate with the second substrate. The method also includes coupling the first substrate with the second substrate by contacting the first surface with the second surface and bonding the first surface with the second surface.

Claims

1. A method for bonding substrates together to manufacture display devices for visual imaging applications, the method comprising:

providing a first substrate comprising a first surface, the first substrate comprising a plurality of first chips thereon, each of the chips comprising integrated circuit devices, the first substrate comprising a first alignment mark on the first substrate and a second alignment mark on the first substrate;

providing a second substrate comprising a silicon bearing material and second surface, the second substrate comprising a plurality of second chips thereon, each of the chips comprising a plurality of mechanical structures, the second substrate comprising a first silicon based pattern on the second substrate and a second silicon based pattern on the second substrate;

holding the first substrate with a first vacuum chuck to substantially contact a backside of the first substrate to the first vacuum chuck;

holding the second substrate with a second vacuum chuck to substantially contact a backside of the second substrate to the second vacuum chuck;

moving the first alignment mark of the first substrate to the first silicon based pattern on the second substrate and aligning the second alignment mark of the first substrate to the second silicon based pattern on the second substrate;

maintaining the first alignment mark of the first substrate within about 40 microns or less of the first silicon based pattern on the second substrate;

maintaining the second alignment mark of the first substrate within about 40 microns or less of the second silicon based pattern on the second substrate;

illuminating a portion of at least one of the first substrate or the second substrate with electromagnetic radiation;

detecting a portion of the electromagnetic radiation;

using the detected portion of the electromagnetic radiation to align the first substrate with the second substrate;

coupling the first substrate with the second substrate by contacting the first surface with the second surface; and

bonding the first surface with the second surface.

2. The method of claim 1 wherein the electromagnetic radiation comprises infrared radiation.

3. The method of claim 1 wherein the first alignment mark and the second alignment mark comprise patterned aluminum.

4. The method of claim 1 wherein the coupling brings the first face in contact with the second face using an action in a direction normal to the first surface and the second surface.

5. The method of claim 4 wherein the coupling occurs using only the normal direction for a distance of less than 30 microns.

6. The method of claim 1 wherein the bonding occurs using room temperature.

7. The method of claim 1 wherein the bonding further comprises annealing the first substrate and the second substrate to permanently bond the first surface to the second surface.

8. The method of claim 1 wherein the first surface comprises a deposited oxide, the deposited oxide being planarized.

9. The method of claim 1 wherein the second surface comprises a polished silicon bearing surface.

10. The method of claim 1 further comprising reducing a thickness of the second substrate to a predetermined thickness.

11. The method of claim 1 wherein each of the plurality of second chips comprises a plurality of mirror structures, each of the mirror structures being separated by a post structure, each of the post structures having a width of about 1 micron and less.

12. A method for bonding different substrates together to manufacture display devices for visual imaging applications, the method comprising:

providing a first substrate comprising a first surface, the first substrate comprising a plurality of first chips thereon, each of the chips comprising integrated circuit devices, the first substrate comprising a first alignment mark on the first substrate and a second alignment mark on the first substrate;

providing a second substrate comprising a second surface, the second substrate comprising a plurality of second chips thereon, each of the chips comprising a plurality of mechanical mirror structures, the second substrate comprising a first pattern on the second substrate and a second pattern on the second substrate;

moving the first alignment mark of the first substrate to the first pattern on the second substrate;

moving the second alignment mark of the first substrate to the second pattern on the second substrate;

maintaining substantial parallel alignment between the first surface and the second surface during a portion of time associated with moving the first alignment mark to the first pattern and moving the second alignment mark with the second pattern;

illuminating a portion of at least one of the first substrate or the second substrate with electromagnetic radiation while the first surface is in substantial parallel alignment with the second substrate;

detecting a signal associated with a portion of the electromagnetic radiation;

using the signal associated with the detected portion of the electromagnetic radiation to align the first substrate with the second substrate using at least the first alignment mark and the first pattern or the second alignment mark and the second pattern;

coupling the first substrate with the second substrate by contacting the first surface with the second surface; and

initiating a bond between the first surface with the second surface.

13. The method of claim 12 wherein the electromagnetic radiation comprises infrared radiation.

14. The method of claim 12 wherein the first alignment mark and the second alignment mark comprise patterned aluminum.

15. The method of claim 12 wherein the coupling brings the first face in contact with the second face using an action in a direction normal to the first surface and the second surface.

16. The method of claim 15 wherein the coupling occurs using only the normal direction for a distance of less than 30 microns.

17. The method of claim 12 wherein the bonding occurs using room temperature.

18. The method of claim 12 wherein the bonding further comprises annealing the first substrate and the second substrate to permanently bond the first surface to the second surface.

19. The method of claim 12 wherein the first surface comprises a deposited oxide, the deposited oxide being planarized.

20. The method of claim 12 wherein the second surface comprises a polished silicon bearing surface.

21. The method of claim 12 further comprising reducing a thickness of the second substrate to a predetermined thickness.